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Physics hw help

So i was sick the other day and didn't go to school, now i gotta do my hw but i don't get it.
1)A pilot knows that her plane in landing configuration will glide a horizntal distance of 19km from a height of 2200 meters. A tower is located in a direct line with the local runway. If the pilot glides over the tower with 47 meters to spare, and touches down on the runaway at a point 6.5km from the base of the tower, how high is the tower?
So i think i have to make 2 triangles to find the height of the tower. Triangle one has a base of 19km and height of 2200meters(ill convert later). I'm not too sure what the dimensions for triangle 2 should be, help?

2)If you are traveling at 77mph what is your angular axle speed in RPM? Assume tire diameter is 28 inches.

3)Assume the planet's orbit is circular at a radius 440million kilometers from its star. Determine the speed of the planet(miles/second) around the star if there are 227 earth days in its year.

All help appreciated, thanks.

September 23, 2014

3 Comments • Newest first

MatthewDough

[url=http://i.imgur.com/X9TfiDk.png?1]Ninja'd by long shot, and also take my word for it and don't trust the help I've given[/url]

Reply September 23, 2014
Invictinite

#1:
vertical = 2200m
horizontal = 19000m

vertical = 47 + x
horizontal = 6500

make proportion
2200/19000 = (47 + x) / 6500
solve

idk if it's right.

#2:
circumference = 2*pi*r = 2 * pi * 14 = 28*pi inches
77mph = 81312 inches/min (ty google)

81312 / (28*pi) = 924.37 rotations per minute

idk if it's right either

#3:
radius = 440 * 10^9 meters
circumference = 2 * pi * 440 * 10^9 = 880 * 10^9 * pi meters = 1.71784 * 10^9 miles (ty google)
227 days = 19612800 seconds (ty google)

(1.71784 * 10^9 miles) / (19612800 seconds) = 87.59 miles/second

?

Reply September 23, 2014 - edited
lukiie

Khan academy

Reply September 23, 2014 - edited